Effect of biosolarization using pellets of Brassica carinata on soil-borne pathogens in protected pepper crops.

摘要

Phytophthora spp. and Meloidogyne incognita are the main soil-borne pathogens of greenhouse pepper crops in Southeast Spain. Between 1985 and 2005, soils were disinfested every year with methyl bromide (MB). Nowadays, among the different alternatives to MB, biosolarization with fresh sheep manure (FSM) is applied at 450 ha, using 1.3-dicholoropropene+chloropicrin (1.3-D+pic) in the rest of surface (1,500 ha). Disinfestant efficacy of biosolarization with Brassica carinata pellets at 300 g m-2 alone or mixed with FSM in different dates of application has been evaluated at experimental and commercial greenhouses. When biosolarization was carried out in August, the survival of P. capsici oospores was as low as MB and the incidence of Meloidogyne was similar to MB (Nodulation Index (NI=0.0; percentage of infested plants IP=0%)). When pellets were mixed with FSM, results showed NI=0.5; IP=13% although incidence using pellets alone (NI=2.3; IP=47%) was inferior to FSM alone (NI=4.1; IP=87%) that improved the control (NI=5.6; IP=100%). When biosolarization was initiated in October, disinfestant efficacy decreased, since the incidence of Meloidogyne and the survival of P. capsici inoculum increased using either pellets alone or mixed with manure.